Safety
Safety across business lines
Safety guides every part of our work, from clean power generation to fuel recycling and isotope production. We design our systems to take advantage of inherent and passive safety characteristics, supported by engineering controls, continuous monitoring, operating procedures, and applicable regulatory oversight. Across our business lines, we prioritize simple system design, predictable responses, and well-understood technologies. This approach is intended to support stable operations and responsible long-term deployment at scale.
A strong foundation in nuclear safety
Nuclear power has accumulated decades of operating experience and established extensive safety practices, technical standards, and regulatory requirements. At Oklo, we build on this foundation by combining established reactor physics with modern manufacturing and monitoring practices.
Safety principles
Inherent and passive safety
Our reactor systems rely on physical properties that naturally regulate behavior. As temperatures change, reactor power and heat flow respond in predictable ways that guide systems toward safe conditions.
Low-pressure design
Key systems operate at or near ambient pressure, reducing mechanical stress and supporting robust confinement. As temperatures rise, inherent feedbacks reduce the fission rate, helping return the reactor toward a stable condition.
Passive heat removal
The Aurora powerhouse is designed to remove decay heat through natural circulation and passive heat transfer. These mechanisms continue to function without external power or continuous operator action.
Layered protection
Facilities incorporate multiple layers of physical barriers, monitoring, and operational controls to protect workers, the public, and the environment.
Safety in power operations
Oklo’s Aurora powerhouses apply these principles and build on decades of fast reactor operating experience and testing worldwide.
Key safety characteristics include:
- Self-stabilizing reactor behavior as temperatures rise
- Automatic shutdown responses without operator intervention
- Passive removal of decay heat after shutdown
- Multiple physical barriers and monitoring systems
A closer look:The self-stabilizing design
A closer look:The self-stabilizing design
The liquid metal coolant circulates on its own as it heats up.
Liquid sodium carries heat away from the core in a closed loop. In the event of power loss or pump failure, high-temperature sodium naturally moves away from the core without relying on active systems for safety.
The reactor core self-adjusts to stay stable.
As core temperature rises, the metal fuel expands and reduces reactivity, which lowers power until the reactor settles at a new, steady state. If external power is lost, the control assemblies drop into the core automatically, shutting down the reactor.
Air pathways remove heat.
After shutdown, decay heat continues to be generated and needs to be shed. Air is pulled in naturally over the outside of the vessel, removes the heat via convection, and carries that heat outside the powerhouse, no fans or electricity required.
The reactor is enclosed in a low-pressure environment.
The reactor core and coolant are sealed in a double-walled vessel at near ambient pressure, which minimizes stress on key components, allows for simpler design, and increases overall safety.
Safety in fuel recycling
By operating within controlled environments and established safeguards, our fuel recycling activities are designed to protect workers, surrounding communities, and the environment through controlled environments, engineered systems, and established safeguards.
Safety measures and safeguards will include:
- Secure handling of used nuclear material within purpose-built facilities
- Near-real-time monitoring of nuclear material control and accounting
- Processes designed to recover plutonium together with other elements rather than producing a separate stream of pure plutonium
- Compliance with long-standing applicable safeguards and nonproliferation requirements
- Electrochemical processes designed to avoid the creation of large liquid waste streams
Safety in isotope production
Isotope production will use dedicated reactors and processing systems designed for reliability and containment. This approach supports consistent supply while maintaining strong safety performance.
Safety and safeguard measures will include:
Defined operating procedures
Controlled processing environments
Regulatory oversight appropriate to each facility and activity
Engineered containment systems
Radiation shielding and monitoring appropriate to the materials handled
Oversight, monitoring, and operations
All Oklo facilities are subject to the applicable U.S. regulatory framework for their purpose and authorization pathway. Some facilities operate under DOE authorization, while others operate under licenses issued by, or oversight from, the U.S. Nuclear Regulatory Commission or other applicable regulatory authorities.
Our facilities are designed to incorporate continuous monitoring, trained operators, and well-defined operating procedures. Safety systems are reviewed and tested throughout design, construction, and operation.
What this means for communities
For communities near our facilities, safety means designing facilities that reduce the likelihood of incidents, limit their consequences, and protect workers, the public, and the environment. Oklo’s facilities are designed to use multiple physical barriers, continuous monitoring, trained personnel, and established procedures to identify and respond to abnormal conditions.
Each facility is reviewed under the regulatory framework applicable to its activities. We work with relevant authorities and local organizations on emergency planning, environmental protection, and community communication.
Across clean power, fuel recycling, and isotope production, our approach is to operate responsibly, protect surrounding communities and the environment, and maintain clear accountability throughout the life of each facility.
